Generally, there are two data storage manners, flash memory storage and hard disk storage. A flash memory has a high access speed, a small capacity, and a high price. A hard disk has a low access speed, but has a large capacity and a low price. Based on this, at present, there exists a new storage manner, that is, a nanowire track racetrack memory, which has features including high performance of a flash memory and a low cost and a high capacity of a hard disk at the same time.
An existing nanowire track is made of magnetic materials and includes multiple magnetic areas, that is, magnetic domains, where neighboring magnetic domains are separated by a magnetic domain wall, and the multiple magnetic areas and the magnetic domain walls form a U-shaped storage track. A high-voltage drive circuit is disposed at two ends of the top of the track, to generate a current pulse that drives the magnetic domain walls to move, and the magnetic domain walls move along the track under an action of the current pulse such that the magnetic domains move. A pair of write and read apparatuses is disposed at the bottom of the track in order to perform read and write control on the U-shaped storage track.
If a U-shaped nanowire track includes 2N magnetic domains (N is a positive integer greater than or equal to 1), when the magnetic domain wall moves, a right track needs to accommodate data information of a left track, and therefore, the 2N magnetic domains may store only N-bit data, and storage density is low, to drive 2N magnetic domain walls to move along the magnetic track, a voltage applied to the high-voltage drive circuit at the two ends of the top of the track is high, and therefore power consumption of a memory is large. In addition, a pair of read and write apparatuses controls only two memory bars in the magnetic track, and therefore production costs are relatively high.